The present invention relates generally to fuel cell bonding and, more particularly, to an apparatus and method for separating a membrane electrode assembly (MEA) from a bonding fixture during automated fuel cell assembly.
A variety of techniques have been developed for laminating stacks of thin layers of materials, such as fuel cell layers. Conventional lamination approaches, for example, often involve subjecting a stack of thin material layers to pressure and heat, such as by use of a bonding press. It is often desirable to automate, either partially or completely, a number of stack processing operations, including stacking, bonding, and cutting operations, for example. Many conventional material stacking, bonding, and cutting apparatuses are not well suited for achieving a high level of automation. This is particularly the case for automated processes which have tight positional tolerance requirements at all stages of processing.
In the case of automated bonding and cutting of a stack of thin material layers, for example, it is necessary to maintain positional continuity of the stack as the stack is processed and moved from the bonding station to the cutting station. This requirement for positional predictability significantly complicates the objective of automating the stack bonding and cutting processes.
There is a need for improved material layer bonding apparatuses and fixtures. There is a further need for an improved apparatus and method for automatically extracting a stack assembly subsequent to a bonding or curing cycle. The present invention fulfills these and other needs.
The present invention is directed to an apparatus and method for separating a membrane electrode assembly (MEA) from a fixture assembly subsequent to MEA bonding within the fixture assembly. The fixture assembly includes a first fixture that contacts a first surface of the MEA and a second fixture that contacts a second surface of the MEA. The first and second fixtures include substantially porous regions, respectively.
The separation apparatus includes a base comprising a first port. The base is adapted to receive the fixture assembly, such that the first port is in fluid communication with a first surface of the MEA via the porous region of the first fixture.
The separation apparatus further includes a gripper assembly mounted for movement on a support. The gripper assembly includes a gripper mechanism and a second port. The second port is in fluid communication with a second surface of the MEA via the porous region of the second fixture. The first and second ports are selectively pressurized and evacuated to separate the first and second surfaces of the MEA from the first and second fixtures, respectively. The gripper assembly is adapted to releasably grip a pair of opposing edges of the second fixture and to move the second fixture out of proximity with the first fixture.
In accordance with a method of separating a membrane electrode assembly from a fixture assembly subsequent to MEA bonding within the fixture assembly, the first fixture of the fixture assembly is initially stabilized. The second fixture of the fixture assembly is stabilized. While the second fixture is stabilized, the first fixture is pressurized to cause the first surface of the MEA to separate from the first fixture. While the first fixture is stabilized, the second fixture is pressurized to cause the second surface of the MEA to separate from the second fixture. According to one particular approach, a vacuum is applied to the second fixture and second surface of the MEA while pressure is being applied to the first fixture and first surface of the MEA, and, subsequently, vacuum is applied to the first fixture and first surface of the MEA while pressure is being applied to the second fixture and second surface of the MEA. The second fixture is then moved out of proximity with the first fixture to permit removal of the MEA from the first fixture.
The above summary of the present invention is not intended to describe each embodiment or every implementation of the present invention. Advantages and attainments, together with a more complete understanding of the invention, will become apparent and appreciated by referring to the following detailed description and claims taken in conjunction with the accompanying drawings.